JP4079074B2 - VEHICLE DRIVE OPERATION ASSISTANCE DEVICE AND VEHICLE HAVING VEHICLE DRIVE OPERATION ASSISTANCE DEVICE - Google Patents

Description

  The present invention relates to a driving operation assisting device for a vehicle that assists a driver's operation.

  A conventional vehicle driving operation assisting device changes an operation reaction force of an accelerator pedal based on an inter-vehicle distance between a preceding vehicle and the host vehicle (see, for example, Patent Document 1). This device alerts the driver by increasing the reaction force of the accelerator pedal as the inter-vehicle distance decreases.

Prior art documents related to the present invention include the following.

Japanese Patent Laid-Open No. 10-166889 Japanese Patent Laid-Open No. 10-166890 JP 2000-54860 A

  In such a driving assistance device for a vehicle, the driver's risk sense matches the reaction force generated in the accelerator pedal even when the movement state or vehicle state of the host vehicle changes. It is desired to perform reaction force control that suits the risk to be felt.

The vehicle driving operation assisting device according to the present invention includes, as an obstacle situation around the own vehicle, a situation recognition means for detecting the own vehicle speed, an inter-vehicle distance between the own vehicle and a preceding vehicle, and a relative speed , and a movement state of the own vehicle itself. A surrounding situation risk that represents a risk due to the relative positional relationship between the host vehicle and the preceding vehicle based on the obstacle state detected by the movement state detecting means for detecting at least one of longitudinal acceleration and lateral acceleration and the situation recognition means Ambient condition risk potential calculation means for calculating a potential, a movement condition risk potential calculation means for calculating a movement state risk potential based on the movement state of the vehicle itself, and a surrounding situation risk potential calculated by the surrounding situation risk potential calculation means And the motion state calculated by the motion state risk potential calculation means A selection means for selecting the larger risk risk as a risk potential for control from the risk potential, and an operation reaction force control for controlling an operation reaction force generated in the vehicle operating device based on the risk potential selected by the selection means. Means.

According to the present invention, there is provided a vehicular driving assist device that detects a vehicle speed, a vehicle speed, a distance recognition between the vehicle and a preceding vehicle, and a relative speed as an obstacle situation around the vehicle, and a vehicle of the vehicle including an occupant. Vehicle weight detection means for detecting weight, risk potential calculation means for calculating a risk potential representing a risk due to a relative positional relationship between the host vehicle and the preceding vehicle based on an obstacle situation detected by the situation recognition means, and a vehicle Based on the vehicle weight detected by the weight detection means, the risk potential correction means for correcting the risk potential so that the risk potential calculated by the risk potential calculation means decreases as the vehicle weight increases, and the risk potential correction means Based on the corrected risk potential, Operation for controlling the operation reaction force and a reaction force control means.

  According to the vehicle driving operation assistance device of the present invention, the motion state risk potential that detects the motion state of the host vehicle that changes the driver's risk feeling and calculates based on the detection result, and the risk potential around the host vehicle. Therefore, since the reaction force control is performed by selecting the larger value, the risk potential that matches the risk felt by the driver can be transmitted to the driver.

  According to the vehicular driving operation assisting device of the present invention, the risk potential around the host vehicle is corrected based on the vehicle weight, so that the acceleration feeling felt by the driver and the operation reaction force of the vehicle operating device can be balanced. .

<< First Embodiment >>
FIG. 1 is a system diagram showing a configuration of a vehicle driving assistance device 1 according to the first embodiment of the present invention, and FIG. 2 is a configuration diagram of a vehicle on which the vehicle driving assistance device 1 is mounted. .

  First, the configuration of the vehicle driving assistance device 1 will be described. The laser radar 10 is attached to a front grill part or a bumper part of the vehicle, and scans the front area of the host vehicle by irradiating infrared light pulses in the horizontal direction. The laser radar 10 measures the reflected wave of the infrared light pulse reflected by a plurality of reflectors in front (usually the rear end of the preceding vehicle), and determines the inter-vehicle distance to the preceding vehicle from the arrival time of the reflected wave. Detect relative speed. The detected inter-vehicle distance and relative speed are output to the controller 50. The forward area scanned by the laser radar 10 is about ± 6 deg with respect to the front of the host vehicle, and a forward object existing within this range is detected.

The vehicle speed sensor 20 detects the vehicle speed of the host vehicle by measuring the number of rotations of the wheels and the number of rotations on the output side of the transmission, and outputs the detected host vehicle speed to the controller 50.
The vehicle state detection device 30 detects the motion state of the host vehicle. In the first embodiment, the vehicle state detection device 30 is a longitudinal acceleration sensor that detects acceleration in the longitudinal direction of the vehicle. The vehicle state detection device 30 outputs the detected longitudinal acceleration to the controller 50.

  The controller 50 includes a CPU and CPU peripheral components such as a ROM and a RAM, and performs overall control of the vehicle driving assistance device 1. The controller 50 calculates the risk potential around the host vehicle from signals such as the host vehicle speed, the inter-vehicle distance, and the relative speed input from the vehicle speed sensor 20 and the laser radar 10. In addition, the risk potential is corrected so that the driver's sense of risk based on the motion state of the host vehicle detected by the vehicle state detection device 30 matches the calculated risk potential. Further, in order to perform accelerator pedal reaction force control based on the corrected risk potential, a reaction force command value is output to the accelerator pedal reaction force control device 60. The calculation of the risk potential and the accelerator pedal reaction force control by the controller 50 will be described later.

  The accelerator pedal reaction force control device 60 controls the accelerator pedal operation reaction force according to a command value from the controller 50. As shown in FIG. 3, the accelerator pedal 80 is connected to a servo motor 70 and an accelerator pedal stroke sensor 71 via a link mechanism. The servo motor 70 controls the torque and the rotation angle in accordance with a command from the accelerator pedal reaction force control device 60, and arbitrarily controls the operation reaction force generated when the driver operates the accelerator pedal 80. The accelerator pedal stroke sensor 71 detects the stroke amount S of the accelerator pedal 80 converted into the rotation angle of the servo motor 70 via the link mechanism.

  Note that the normal accelerator pedal reaction force characteristic Fi when the accelerator pedal reaction force control is not performed is set, for example, such that the accelerator pedal reaction force increases linearly as the stroke amount S increases (see FIG. 8). The normal accelerator pedal reaction force characteristic Fi can be realized by a spring force of a torsion spring (not shown) provided at the center of rotation of the accelerator pedal 80, for example.

Next, the operation of the vehicle driving assistance device 1 according to the first embodiment of the present invention will be described. First, the outline will be described below.
The controller 50 calculates the risk potential RP around the host vehicle based on the obstacle situation around the host vehicle. Then, an operation reaction force F corresponding to the calculated risk potential RP is generated in the accelerator pedal 80. Here, when the accelerator pedal reaction force control is performed based on the risk potential RP around the host vehicle, it is desirable to transmit the risk actually felt by the driver to the driver as the accelerator pedal reaction force F.

  The risk that the driver actually feels during traveling varies depending on the traveling conditions around the host vehicle. For example, even when the relative speed vr and the inter-vehicle distance d are the same between the host vehicle and the preceding vehicle at a certain point in time, the relative speed vr is 0, the inter-vehicle distance d is constant, and the host vehicle follows the preceding vehicle. The risk perceived by the driver differs between the steady state and the case where the relative speed vr and the inter-vehicle distance d vary and the host vehicle approaches the preceding vehicle, that is, the transient state. Furthermore, the risk that the driver feels also changes depending on the movement state of the host vehicle.

  Therefore, in the first embodiment, the risk when the driving situation around the host vehicle is in a steady state and the risk when it is in a transient state are separately defined, and the risk potential that matches the driver's sense is calculated. To do. Furthermore, a change in the risk felt by the driver due to a change in the motion state of the host vehicle is estimated, and the risk potential is corrected according to the change in the driver's risk feeling. Specifically, the risk potential that is actually used for control is calculated by Select High from the risk potential calculated from the steady state risk and the transient state risk, and the risk potential according to the vehicle motion state.

  Below, operation | movement of the driving operation assistance apparatus 1 for vehicles by 1st Embodiment is demonstrated in detail using FIG. FIG. 4 is a flowchart showing a processing procedure of the driving operation assistance control program in the controller 50. This processing content is continuously performed at regular intervals (for example, 50 msec).

  In step S110, the host vehicle and the traveling state around the vehicle are read from the laser radar 10 and the vehicle speed sensor 20. FIG. 5 schematically shows the running state of the host vehicle and the preceding vehicle ahead of the host vehicle. Parameters indicating the traveling state of the host vehicle are the current position x1 and the host vehicle speed v1 of the host vehicle in the vehicle front-rear direction. The parameters indicating the traveling state of the preceding vehicle are the current position x2 and the preceding vehicle speed v2 of the preceding vehicle in the vehicle front-rear direction. The inter-vehicle distance d between the host vehicle and the preceding vehicle is expressed as d = x2-x1, and the relative speed vr is expressed as vr = v2-v1.

  In step S120, the motion state of the host vehicle is detected in order to estimate a change in the driver's risk feeling. Here, the longitudinal acceleration a of the host vehicle detected by the longitudinal acceleration sensor 30 is read as the vehicle motion state. When the longitudinal acceleration a of the host vehicle is high, it can be estimated that the driver feels a great risk.

  In step S130, the risk potential (steady term) RPsteady when the driving situation around the host vehicle is in a steady state and the risk potential (transient term) transient when in a transient state are calculated, respectively, and the risk potential for the preceding vehicle is calculated. Is calculated. Hereinafter, the risk potential calculated from the steady term RPsteady and the transient term RPtransient is represented as RPoriginal. In order to calculate the steady term RPsteady and the transient term RPtransient, first, the margin time TTC and the inter-vehicle time THW for the preceding vehicle are calculated.

The margin time TTC is a physical quantity indicating the current degree of proximity of the host vehicle with respect to the preceding vehicle. In the allowance time TTC, when the current traveling state continues, that is, when the own vehicle speed v1, the preceding vehicle speed v2, and the relative vehicle speed vr are constant, the inter-vehicle distance d becomes zero and the own vehicle and the preceding vehicle come into contact with each other. It is a value indicating The margin time TTC is obtained by the following (Equation 1).
TTC = −d / vr (Formula 1)

  The smaller the margin time TTC value, the closer the contact with the preceding vehicle, and the greater the degree of approach to the preceding vehicle. For example, when approaching a preceding vehicle, it is known that most drivers start a deceleration action before the margin time TTC becomes 4 seconds or less.

The inter-vehicle time THW is an effect when it is assumed that the degree of influence on the margin time TTC due to a change in the vehicle speed of the assumed vehicle ahead, that is, the relative vehicle speed vr changes when the host vehicle follows the preceding vehicle. It is a physical quantity indicating the degree. The inter-vehicle time THW is expressed by the following (Formula 2).
THW = d / v1 (Formula 2)

  The inter-vehicle time THW is obtained by dividing the inter-vehicle distance d by the own vehicle speed v1, and indicates the time until the own vehicle reaches the current position of the preceding vehicle. The greater the inter-vehicle time THW, the smaller the predicted influence level with respect to the surrounding environmental changes. That is, when the inter-vehicle time THW is large, even if the vehicle speed of the preceding vehicle changes in the future, the degree of approach to the preceding vehicle is not greatly affected, and the margin time TTC does not change so much. When the own vehicle follows the preceding vehicle and the own vehicle speed v1 = the preceding vehicle speed v2, the inter-vehicle time THW can be calculated using the preceding vehicle speed v2 instead of the own vehicle speed v1 in (Equation 2).

The steady term RPsteady and the transient term RPtransient are expressed as shown in the following (Equation 3) and (Equation 4) using the inter-vehicle time THW calculated from (Equation 2) and the margin time TTC calculated from (Equation 1). Is done.
RPsteady = 1 / THW (Formula 3)
RPtransient = 1 / TTC (Formula 4)

Further, the risk potential RPoriginal for the preceding vehicle is calculated using the calculated steady term RPsteady and transient term RPtransient.
The risk potential RPoriginal for the preceding vehicle can be calculated using the following (Formula 5).
RPoriginal = A ・ RPsteady + B ・ RPtransient (Formula 5)
Here, A and B are constants for appropriately weighting the steady term RPsteady and the transient term RPtransient, and appropriate values are set in advance. The constants A and B are set to A = 1, B = 8 (A <B), for example.

  In subsequent step S140, a risk potential RPvd corresponding to the driver's risk feeling due to the vehicle motion state is calculated. Specifically, the risk potential RPvd is calculated based on the longitudinal acceleration a of the host vehicle detected in step S120. FIG. 6 shows the relationship between the longitudinal acceleration a and the risk potential RPvd.

As shown in FIG. 6, the longitudinal acceleration a is divided into regions A to E, and the risk potential RPvd corresponding to the longitudinal acceleration a is calculated in each region. First, the range of longitudinal acceleration a that occurs in normal driving traveling without sudden acceleration or deceleration is defined as region A (0 ≦ a <a1). In the region A, the risk potential RPvd gradually increases as the longitudinal acceleration a increases. Here, the predetermined value a1 is, for example, a1 = 1.0 m / s ² .

In the region B (a1 ≦ a <a2), the risk potential RPvd greatly increases as the longitudinal acceleration a increases. The slope of the risk potential RPvd with respect to the longitudinal acceleration a in the region B is set larger than that in the region A. The predetermined value a2 is set, for example, as a2 = 2.0 m / s ² . When the longitudinal acceleration a is within the range B, the risk potential RPvd is set to be large so that it is determined that the vehicle is overaccelerated with respect to normal driving, and the driver's attention is lowered to reduce the vehicle speed. To do.

  In the region C (a> a2), the risk potential RPvd is fixed to a maximum value, for example, RPvd = 2. When the longitudinal acceleration a is in the region C, it is determined that the current vehicle motion state is close to the vehicle motion limit. In such a state, the risk potential RPvd is set to a fixed value in order to suppress an increase in the accelerator pedal reaction force that hinders the driver's accelerator pedal operation.

  When the longitudinal acceleration a in the area C decreases, the process proceeds to the area D (a1 ≦ a <a2) in order to give the risk potential RPvd hysteresis. In the region D, the risk potential RPvd is suddenly decreased when the longitudinal acceleration a falls below the predetermined value a2 from the state where the risk potential RPvd is high in the region C and a large accelerator pedal reaction force is generated. In order to prevent the light from suddenly becoming light, the risk potential RPvd is held at the maximum value.

When the longitudinal acceleration a decreases from the region D to E, it is determined that the longitudinal acceleration a has decreased to a level during normal driving, and the risk potential RPvd is decreased as the longitudinal acceleration a decreases.
The controller 50 stores the previous longitudinal acceleration a region in order to determine which region the longitudinal acceleration a is currently in.

Thus, after calculating the risk potential RPvd according to the longitudinal acceleration a in step S140, the process proceeds to step 150. In step S150, the risk potential RP used in the actual control is calculated by the select high from the risk potential RPoriginal for the preceding vehicle calculated in step S130 and the risk potential RPvd corresponding to the longitudinal acceleration a calculated in step S140. The risk potential RP is expressed by the following (formula 6).
RP = max (RPoriginal, RPvd) (Formula 6)

  In step S160, the accelerator pedal reaction force increase amount dF is calculated based on the risk potential RP calculated in step S150. FIG. 7 shows the relationship between the risk potential RP and the accelerator pedal reaction force increase amount dF. As shown in FIG. 7, the accelerator pedal reaction force increase amount dF increases as the risk potential RP increases. When the risk potential RP exceeds the maximum value RPmax, the reaction force increase amount is fixed to the maximum value dFmax.

  Thus, until the risk potential RP reaches the maximum value RPmax, the accelerator pedal reaction force transmits the risk potential RP around the host vehicle to the driver, and in a situation where the risk potential RP exceeds the maximum value RPmax, the accelerator pedal By limiting the increase in the reaction force increase amount dF, a driving operation such as overtaking can be performed according to the driver's intention. The risk potential maximum value RPmax is preferably set to the same value as the risk potential RPvd (for example, RPvd = 2) when the longitudinal acceleration a is in the region C or D. Thereby, when the longitudinal acceleration a is in the region C or D, the reaction force increase amount dF can be fixed to the maximum value to suppress the fluctuation of the accelerator pedal reaction force.

  In step S170, the reaction force increase amount dF calculated in step S160 is output to the accelerator pedal reaction force control device 60. In response to a command from the controller 50, the accelerator pedal reaction force control device 60 generates an accelerator pedal reaction force F obtained by adding the reaction force increase amount dF to the normal reaction force characteristic Fi as shown in FIG. The servo motor 70 is controlled. Thus, the current process is terminated.

Thus, in the first embodiment described above, the following operational effects can be achieved.
(1) The controller 50 calculates the risk potential RPoriginal (ambient situation risk potential) around the host vehicle based on the vehicle state of the host vehicle and the traveling environment around the host vehicle, and uses the calculated risk potential RPoriginal as the motion of the host vehicle. Correct based on condition. Specifically, the controller 50 calculates a risk potential RPvd (exercise state risk potential) based on the motion state of the host vehicle, and selects a risk potential RP having a larger value from RPoriginal and RPvd by select high. Then, the reaction force increase amount dF is calculated based on the selected risk potential RP, and the operation reaction force generated in the vehicle operating device, specifically, the accelerator pedal 80 is controlled. As a result, the risk potential RP can be calculated in consideration of the driver's sense of risk that changes depending on the motion state of the host vehicle, and the accelerator pedal reaction force control suitable for the risk felt by the driver can be performed. In addition, since the larger value is selected from the risk potential RPoriginal for the preceding vehicle and the risk potential RPvd based on the motion state, accelerator pedal reaction force control that is easy for the driver to understand can be performed.
(2) The controller 50 detects the longitudinal acceleration a of the host vehicle, and calculates the risk potential RPvd based on the longitudinal acceleration a. Thereby, it becomes possible to set the risk potential RP corresponding to the vehicle motion in the front-rear direction of the host vehicle, and appropriate accelerator pedal reaction force control suitable for the driver's feeling can be performed.
(3) As shown in FIG. 6, when the longitudinal acceleration a exceeds the predetermined value a1, the amount of change in the risk potential RPvd with respect to the longitudinal acceleration a is increased as compared with the case where the longitudinal acceleration a is equal to or less than the predetermined value a1. . As a result, when the longitudinal acceleration a is in the region B and the vehicle is over-accelerated compared to normal driving, a large risk potential RP can be set. As a result, the accelerator pedal reaction force is increased to alert the driver, and the driver's sense of risk that has decreased while the host vehicle is accelerating can be returned to an appropriate state.
(4) When the longitudinal acceleration a exceeds the maximum value a2, the change of the risk potential RPvd with respect to the longitudinal acceleration a is suppressed as shown in FIG. Thus, when the longitudinal acceleration a is in the region C and it can be determined that the motion state in the longitudinal direction of the host vehicle is approaching the motion limit, it is possible to suppress an increase in the risk potential RP. As a result, since the accelerator pedal reaction force does not increase more than necessary, the pedal operation by the driver is not hindered.
(5) When the longitudinal acceleration a falls below the maximum value a from the state where the maximum value a2 is exceeded, the risk potential RPvd with respect to the longitudinal acceleration a is provided with hysteresis. Specifically, the risk potential RPvd is held at the maximum value when shifting from the region C to the region D as shown in FIG. As a result, it is possible to prevent the risk potential RP from abruptly decreasing when the longitudinal acceleration a decreases below the maximum value a2, and to perform stable accelerator pedal reaction force control.

<< Second Embodiment >>
Below, the driving assistance device for vehicles in the 2nd Embodiment of this invention is demonstrated. The configuration of the vehicular driving assist device in the second embodiment is the same as that of the first embodiment shown in FIGS. 1 and 2. Here, differences from the first embodiment will be mainly described.

  In the second embodiment, the lateral acceleration of the host vehicle is detected as the vehicle motion state in order to estimate the change in the driver's sense of risk. Here, the vehicle state detection device 30 is a lateral acceleration sensor that detects vehicle lateral acceleration, and outputs the detected vehicle lateral acceleration to the controller 50.

FIG. 9 shows the relationship between the lateral acceleration ay and the risk potential RPvd.
As shown in FIG. 9, the lateral acceleration ay is divided into regions A to E, and the risk potential RPvd is calculated in each region according to the lateral acceleration ay. First, a region A (0 ≦ ay <ay1) is defined as a range of lateral acceleration that occurs during normal driving such as when the host vehicle is traveling on a straight road or a gentle curve. In the region A, the risk potential RPvd gradually increases as the lateral acceleration ay increases. Here, the predetermined value ay1 is, for example, ay1 = 2.0 m / s ² .

In the region B (ay1 ≦ ay <ay2), the risk potential RPvd greatly increases as the lateral acceleration ay increases. The slope of the risk potential RPvd with respect to the lateral acceleration ay in the region B is set larger than that in the region A. The predetermined value ay2 is set, for example, as ay2 = 4.0 m / s ² . When the lateral acceleration ay is in the range of the region B, it is determined that excessive lateral acceleration ay has occurred with respect to normal driving and a risk that the driver's attention is lowered to reduce the vehicle speed. The potential RPvd is set large.

  In the region C (ay> ay2), the risk potential RPvd is fixed to the maximum value, for example, RPvd = 2. When the lateral acceleration ay is in the region C, it is determined that the current vehicle motion state is close to the vehicle motion limit. In such a state, the risk potential RPvd is set to a fixed value in order to suppress an increase in the accelerator pedal reaction force that hinders the driver's accelerator pedal operation.

  When the lateral acceleration ay in the region C decreases, the process proceeds to the region D (ay1 ≦ ay <ay2) in order to give the risk potential RPvd hysteresis. In the region D, since the risk potential RPvd is high in the region C and a large accelerator pedal reaction force is generated, the risk potential RPvd sharply decreases when the lateral acceleration ay falls below the predetermined value ay2, and the accelerator pedal reaction force In order to prevent the light from suddenly becoming light, the risk potential RPvd is held at the maximum value.

When the lateral acceleration ay decreases from the region D to E, it is determined that the lateral acceleration ay has decreased to a level during normal driving, and the risk potential RPvd is decreased as the lateral acceleration ay decreases.
The controller 50 stores the region of the previous lateral acceleration ay in order to determine which region the lateral acceleration ay is currently in.

  After calculating the risk potential RPvd corresponding to the lateral acceleration ay using the map of FIG. 9, the controller 50 calculates the risk potential RP for calculating the reaction force increase dF by select high using (Equation 6). To do.

Thus, in the second embodiment described above, the following operational effects can be obtained in addition to the effects of the first embodiment described above.
(1) The controller 50 detects the lateral acceleration ay of the host vehicle and calculates the risk potential RPvd based on the lateral acceleration ay. As a result, it is possible to set the risk potential RP corresponding to the vehicle motion in the lateral (left and right) direction of the host vehicle, and appropriate accelerator pedal reaction force control suitable for the driver's feeling can be performed.
(2) As shown in FIG. 9, when the lateral acceleration ay exceeds the predetermined value ay1, the amount of change in the risk potential RPvd with respect to the lateral acceleration ay is increased compared to the case where the lateral acceleration ay is equal to or less than the predetermined value ay1. . As a result, when the lateral acceleration ay is in the region B and excessive lateral acceleration ay is generated as compared with normal driving, a large risk potential RP can be set. As a result, the accelerator pedal reaction force can be increased to alert the driver that the speed has been exceeded during turning.
(3) When the lateral acceleration ay exceeds the maximum value ay2, the change in the risk potential RPvd with respect to the lateral acceleration ay is suppressed as shown in FIG. Thereby, when the lateral acceleration ay is in the region C and it can be determined that the motion state in the lateral direction of the host vehicle is approaching the motion limit, it is possible to suppress an increase in the risk potential RP. As a result, since the accelerator pedal reaction force does not increase more than necessary, the pedal operation by the driver is not hindered.
(4) When the lateral acceleration ay drops below the maximum value ay from the state where the maximum value ay2 is exceeded, the risk potential RPvd with respect to the lateral acceleration ay is given hysteresis. Specifically, the risk potential RPvd is held at the maximum value when shifting from the region C to the region D as shown in FIG. As a result, it is possible to prevent the risk potential RP from abruptly decreasing when the lateral acceleration ay decreases below the maximum value ay2, and it is possible to perform stable accelerator pedal reaction force control.

<< Third Embodiment >>
Below, the driving assistance device for vehicles in the 3rd Embodiment of this invention is demonstrated. The configuration of the vehicular driving operation assisting apparatus in the third embodiment is the same as that of the first embodiment shown in FIGS. 1 and 2. Here, differences from the first embodiment will be mainly described.

  In the third embodiment, the weight of the host vehicle is detected in order to estimate a change in the driver's risk. The acceleration feeling of the host vehicle when the accelerator pedal 80 is depressed differs between when the vehicle weight is heavy and when the vehicle weight is light. That is, when the vehicle weight is heavy, even if the accelerator pedal 80 is depressed by the same stroke amount, the acceleration is not as high as when the weight is light, and the reaction force generated in the accelerator pedal 80 is large, but the acceleration feeling felt by the driver is low. An imbalance occurs.

  Therefore, the risk potential is corrected so that a substantially constant accelerator pedal reaction force is generated with respect to the acceleration feeling caused by the accelerator pedal operation regardless of the vehicle weight. Here, the vehicle state detection device 30 includes, for example, a sensor that detects a suspension stroke and a wheel load sensor that detects each wheel load, and detects the current vehicle weight from the detected suspension stroke and wheel load.

  In the third embodiment, the risk potential RPvd is calculated according to the vehicle weight, and the risk potential RPoriginal for the preceding vehicle is corrected using the risk potential RPvd. Specifically, the risk potential RP actually used for control is calculated by adding RPvd to the risk potential RPoriginal.

  FIG. 10 shows a map for setting the risk potential RPvd based on the vehicle weight w. As shown in FIG. 10, the risk potential RPvd corresponding to the vehicle weight w is expressed as a negative value, and the risk potential RPvd is set to 0 when the vehicle weight w is a reference value. Here, for example, a value obtained by adding the weight of one driver to the weight of only the vehicle is set as the reference value. The risk potential RPvd decreases as the vehicle weight w increases with respect to the reference value due to an increase in the number of passengers.

Then, the controller 50 calculates the risk potential RP by adding the risk potential RPoriginal and the risk potential RPvd calculated based on the vehicle weight w as shown in the following (Expression 7).
RP = RPoriginal + RPvd (Expression 7)
Since the risk potential RPvd based on the vehicle weight w is a negative value, the risk potential RPoriginal for the preceding vehicle is corrected so as to decrease according to the vehicle weight w.

  The controller 50 calculates the reaction force increase amount dF from the map of FIG. 6 based on the risk potential RP calculated from (Equation 7). As a result, when the vehicle weight w is heavy and the acceleration feeling as expected by the driver cannot be obtained even when the accelerator pedal 80 is depressed, the accelerator pedal reaction force is reduced.

As described above, the following effects can be achieved in the third embodiment described above.
(1) The controller 50 calculates the risk potential RPoriginal around the host vehicle based on the vehicle state of the host vehicle and the traveling environment around the host vehicle, and corrects the calculated risk potential RPoriginal based on the vehicle weight w of the host vehicle. To do. The acceleration generated in the host vehicle and the acceleration feeling felt by the driver vary depending on the vehicle weight w of the host vehicle. Therefore, by correcting the risk potential RPoriginal for the preceding vehicle with the vehicle weight w, it is possible to generate an equivalent accelerator pedal reaction force regardless of a change in acceleration feeling due to a change in the vehicle weight w. Thereby, accelerator pedal reaction force control suitable for the driver's sense can be performed.
(2) As shown in FIG. 10, the controller 50 calculates the risk potential RPvd (correction value) based on the vehicle weight w of the host vehicle, and adds the correction value RPvd to the risk potential RPoriginal for the preceding vehicle. Correct the potential. Accordingly, it is possible to calculate an appropriate risk potential RP that takes into account the driver's feeling that changes depending on the vehicle weight w.

<< Fourth Embodiment >>
Hereinafter, a driving operation assisting device for a vehicle according to a fourth embodiment of the present invention will be described. The configuration of the vehicular driving operation assisting apparatus in the third embodiment is the same as that of the first embodiment shown in FIGS. 1 and 2. Here, differences from the first embodiment will be mainly described.

  Here, the risk potential RP is calculated by combining the first embodiment and the second embodiment described above. FIG. 11 is a flowchart showing the processing procedure of the vehicle driving operation assistance control processing according to the fourth embodiment. This processing content is continuously performed at regular intervals (for example, 50 msec).

  The processing in steps S210 to S230 is the same as steps S110 to S130 in the flowchart of FIG. However, in step S220, both the longitudinal acceleration a and the lateral acceleration ay of the vehicle are read. In step S240, the risk potential RPvd1 based on the longitudinal acceleration a is calculated using FIG. 6, and the risk potential RPvd2 based on the lateral acceleration ay is calculated using FIG.

In step S250, the risk potential RP is calculated by select high from the risk potential RPoriginal for the preceding vehicle calculated in step S230, the risk potential RPvd1 based on the longitudinal acceleration a calculated in step S240, and the risk potential RPvd2 based on the lateral acceleration ay. .
The processes in steps S260 and S270 are the same as steps S160 and S170 in FIG.

  Accordingly, the risk potentials RPvd1 and RPvd2 based on the longitudinal acceleration a and the lateral acceleration ay of the host vehicle are calculated, respectively, and the risk potentials calculated based on the obstacle situation around the host vehicle and the motion state of the host vehicle are calculated. The risk potential RP can be set by selecting the largest value. As a result, the greatest risk at the present time can be transmitted to the driver as the accelerator pedal reaction force.

  Further, as described in the third embodiment, the risk potential RPoriginal corrected according to the vehicle weight w, the risk potential RPvd1 based on the longitudinal acceleration a, and the risk potential RPvd2 based on the lateral acceleration ay are selected by high. The risk potential RP can also be calculated.

  In the first embodiment, the risk potential RPvd for the longitudinal acceleration a is set as shown in FIG. However, the present invention is not limited to this. For example, the risk potential RPvd can be set so as to change smoothly with respect to the change in the longitudinal acceleration a. Similarly, the risk potential RPvd with respect to the lateral acceleration ay is not limited to the map shown in FIG.

  In the first to fourth embodiments described above, the longitudinal acceleration a, the lateral acceleration ay, and the vehicle weight w are used as parameters representing the state of the host vehicle. However, the present invention is not limited to these, and the risk potential RPoriginal for the preceding vehicle can be corrected using other parameters.

  In the first to fourth embodiments described above, the reaction force increase amount dF is set to be proportional to the risk potential RP as shown in FIG. 7, but the present invention is not limited to this. The reaction force increase amount dF can also be set so as to increase exponentially with respect to the increase in RP.

  The vehicle driving assistance device according to the present invention uses the laser radar 10 and the vehicle speed sensor 20 as situation recognition means, and uses the vehicle state detection apparatus 30 as movement state detection means and vehicle weight detection means, and calculates the ambient situation risk potential. The controller 50 was used as means, exercise state risk potential calculation means, selection means, and risk potential correction means. Further, the controller 50 and the accelerator pedal reaction force control device 60 were used as the operation reaction force control means. However, the present invention is not limited to these. For example, instead of the laser radar 10, another type of millimeter wave radar or the like, or a CCD camera or a CMOS camera can be used as the situation recognition means. Further, a brake pedal reaction force control device can be used as the operation reaction force control means, and an operation reaction force corresponding to the risk potential RP can be generated in the brake pedal.

1 is a system diagram of a vehicle driving assistance device according to the present invention. The block diagram of the vehicle carrying the driving operation assistance apparatus for vehicles shown in FIG. The block diagram around an accelerator pedal. The flowchart which shows the process sequence of the driving operation assistance control program by the controller of 1st Embodiment. The schematic diagram which shows the driving state of the own vehicle and a preceding vehicle. The figure which shows the relationship between the longitudinal acceleration and risk potential. The figure which shows the relationship between risk potential and reaction force increase amount. The figure which shows the accelerator pedal reaction force characteristic with respect to the amount of accelerator pedal strokes. The figure which shows the relationship between a lateral acceleration and a risk potential. The figure which shows the relationship between vehicle weight and risk potential. The flowchart which shows the process sequence of the driving operation assistance control program by the controller of 4th Embodiment.

Explanation of symbols

10: laser radar 20: vehicle speed sensor 30: vehicle state detection device 50: controller 60: accelerator pedal reaction force control device 70: servo motor 71: stroke sensor 80: accelerator pedal

Claims (15)

As the obstacle situation around the host vehicle, the situation recognition means for detecting the host vehicle speed , the distance between the host vehicle and the preceding vehicle and the relative speed ,
A motion state detection means for detecting at least one of longitudinal acceleration and lateral acceleration as the motion state of the vehicle itself;
Ambient situation risk potential calculation means for calculating an ambient situation risk potential representing a risk due to a relative positional relationship between the host vehicle and the preceding vehicle based on the obstacle situation detected by the situation recognition means;
A motion state risk potential calculating means for calculating a motion state risk potential based on the motion state of the vehicle itself;
A larger value is selected as a control risk potential from the ambient situation risk potential calculated by the ambient situation risk potential calculation unit and the exercise state risk potential calculated by the exercise state risk potential calculation unit. A selection means;
An operation assisting device for a vehicle, comprising: an operation reaction force control unit that controls an operation reaction force generated in the vehicle operation device based on the risk potential selected by the selection unit. The vehicle driving assistance device according to claim 1,
The motion state detection means detects longitudinal acceleration of the host vehicle ,
The vehicle operation assistance device according to claim 1, wherein the motion state risk potential calculation means calculates the motion state risk potential such that the motion state risk potential increases as the longitudinal acceleration increases . The vehicle driving assistance device according to claim 1,
The motion state detection means detects lateral acceleration of the host vehicle ,
The driving condition assisting device for a vehicle, wherein the athletic condition risk potential calculating means calculates the athletic condition risk potential such that the athletic condition risk potential increases as the lateral acceleration increases . The vehicle driving operation assistance device according to claim 2,
The motion state risk potential calculation means increases the amount of change in the motion state risk potential with respect to the longitudinal acceleration when the longitudinal acceleration exceeds a predetermined value compared to when the longitudinal acceleration is equal to or less than the predetermined value. A driving operation assisting device for a vehicle. The vehicle driving operation assistance device according to claim 2,
The vehicle operation assistance device according to claim 1, wherein the motion state risk potential calculation means suppresses a change in the motion state risk potential with respect to the longitudinal acceleration when the longitudinal acceleration exceeds a maximum value. The vehicle driving operation assistance device according to claim 4,
The motion state risk potential calculating means suppresses a change in the motion state risk potential with respect to the longitudinal acceleration when the longitudinal acceleration exceeds a maximum value larger than the predetermined value. apparatus. In the vehicle driving assistance device according to claim 5 or 6,
The athletic state risk potential calculating means provides hysteresis to the athletic state risk potential with respect to the longitudinal acceleration when the longitudinal acceleration decreases from the state exceeding the maximum value to the maximum value or less. Driving operation assist device for vehicles. The vehicle driving assistance device according to claim 3,
The motion state risk potential calculation means increases the amount of change of the motion state risk potential with respect to the lateral acceleration when the lateral acceleration exceeds a predetermined value compared to when the lateral acceleration is equal to or less than the predetermined value. A driving operation assisting device for a vehicle. The vehicle driving assistance device according to claim 3,
The driving condition assisting device for a vehicle, wherein when the lateral acceleration exceeds a maximum value, the movement state risk potential calculating unit suppresses a change in the movement state risk potential with respect to the lateral acceleration. The vehicle driving operation assistance device according to claim 8,
The motion state risk potential calculating means suppresses a change in the motion state risk potential with respect to the lateral acceleration when the lateral acceleration exceeds a maximum value larger than the predetermined value. apparatus. In the driving assistance device for a vehicle according to claim 9 or 10,
The athletic state risk potential calculating means provides hysteresis to the athletic state risk potential with respect to the lateral acceleration when the lateral acceleration decreases from the state exceeding the maximum value to the maximum value or less. Driving operation assist device for vehicles. The vehicle driving assistance device according to claim 1,
The movement state detection means detects longitudinal acceleration and lateral acceleration of the host vehicle,
The motion state risk potential calculation means calculates a first motion state risk potential that increases as the longitudinal acceleration increases and a second motion state risk potential that increases as the lateral acceleration increases, respectively.
The selection means selects the largest value as the risk potential for control from the ambient situation risk potential, the first motion state risk potential, and the second motion state risk potential. A driving operation assisting device for a vehicle. As the obstacle situation around the host vehicle, the situation recognition means for detecting the host vehicle speed , the distance between the host vehicle and the preceding vehicle and the relative speed ,
Vehicle weight detection means for detecting the vehicle weight of the host vehicle including an occupant ;
Risk potential calculation means for calculating a risk potential representing a risk due to a relative positional relationship between the host vehicle and the preceding vehicle based on the obstacle situation detected by the situation recognition means;
Risk potential correction means for correcting the risk potential so that the risk potential calculated by the risk potential calculation means becomes smaller as the vehicle weight increases based on the vehicle weight detected by the vehicle weight detection means. When,
An operation assistance device for a vehicle, comprising: an operation reaction force control unit that controls an operation reaction force generated in a vehicle operation device based on the risk potential corrected by the risk potential correction unit. The vehicle driving assistance device according to claim 13,
The vehicle driving operation assisting device, wherein the risk potential correction means calculates a correction value based on the vehicle weight, and corrects the risk potential by adding the correction value to the risk potential.   A vehicle comprising the vehicular driving assist device according to any one of claims 1 to 14.

Images